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Override and update your locally modified files through cvs..

Emptying a text file in one shot
% = buffer d = delete

GZip all files in a directory separately

shutdown pc in 4 hours without needing to keep terminal open / user logged in.
From the 'disown' man page: disown prevents the current shell from sending a HUP signal to each of the given jobs when the current shell terminates a login session.

Execute a command at a given time
This is an alternative to cron which allows a one-off task to be scheduled for a certain time.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Tell Analytics to fuck itself.
See http://code.google.com/apis/analytics/docs/concepts/gaConceptsCookies.html if you are unclear about the Google Analytics cookie system. If Firefox is your daily browser, be a good Orwellian and run this command regularly. If you see, 'SQL error near line 1: database is locked', close Firefox and run again.

Stream audio over ssh ogg version
Stream OGG vorbis over ssh.

Functions to display, save and restore $IFS
You can display, save and restore the value of $IFS using conventional Bash commands, but these functions, which you can add to your ~/.bashrc file make it really easy. To display $IFS use the function ifs shown above. In the sample output, you can see that it displays the characters and their hexadecimal equivalent. This function saves it in a variable called $saveIFS: $ sifs () { saveIFS=$IFS; } Use this function to restore it $ rifs () { IFS=$saveIFS; } Add this line in your ~/.bashrc file to save a readonly copy of $IFS: $ declare -r roIFS=$IFS Use this function to restore that one to $IFS $ rrifs () { IFS=$roIFS; }


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